Power delivery over digital interaction interface for video and audio (DiiVA)

ABSTRACT

A system for delivering power over a network of devices connected through a serial link includes a first and second differential pairs of wires. Each differential pair of wires is double AC coupled by a HPF on one side and by another HPF on an opposite side. An LPF connects a portion of each differential pair of wires between the HPFs to a voltage source, and another LPF connects that portion of each differential pair to a load. The system further includes a third and fourth differential pairs of wires. All four differential pairs of wires are located within a single cable, such as a CAT6 cable. The first, second and third differential pair of wires are used for video links, and the fourth differential pair of wires are used for the bi-directional hybrid link. A power delivery circuit in each device includes a voltage source, a power relay switch, a signature resistor for detection, and a load detector.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. application Ser. No.12/636,063 the “'063 application”), filed on Dec. 11, 2009 and entitled“Power Delivery Over Digital Interactive Interface for Video and Audio(DiiVA),” which is based upon, and claims the benefit of priority under35 U.S.C. §119, to U.S. Provisional Patent Application No. 61/201,727(the “'727 provisional application”), filed Dec. 11, 2008 and entitled“Power Delivery Over Digital Interactive Interface for Video and Audio(DiiVA).” The content of both the '063 application and the '717provisional application are incorporated by reference in their entiretyas though fully set forth herein.

BACKGROUND

DiiVA (Digital Interactive Interface For Video And Audio) is abi-directional audio/video interface that allows uncompressedhigh-definition video, as well as multi-channel audio, high-bandwidth,and bi-directional data to be transferred over a single cable. DiiVAimplements a bi-directional hybrid data channel capable of transportinguser data, including but not limited to audio data, control data,Ethernet data, and bulk data. DiiVA allows users to connect, configureand control a plurality of consumer electronic devices (includingwithout limitation DVD players, digital video recorders, set top boxes,personal computers, camcorders, cameras, and home stereo systems, justby way of example) from their digital TV or other DiiVA node.

Methods and systems are needed for reliably delivering power over DiiVA.

SUMMARY

A system for delivering power over a network of devices connectedthrough a serial link includes a first differential pair of wires and asecond differential pair of wires. The first differential pair of wiresis double AC coupled by a first HPF (high pass filter) on one side andby a second HPF on an opposite side. The second differential pair ofwires is double AC coupled by a third HPF on one side and by a fourthHPF on an opposite side. A first LPF (low pass filter) connects aportion of the first differential pair of wires between the first HPFand the second HPF to a voltage source. A second LPF connects theportion of the first differential pair of wires to a load. The systemfurther includes a third differential pair of wires and a fourthdifferential pair of wires. All four differential pairs of wires arelocated within a single cable, such as a CAT6 cable. The first, secondand third differential pair of wires are used for video links, and thefourth differential pair of wires are used for a bi-directional hybridlink.

A power delivery circuit configured to deliver power to one or more of aplurality of devices connected in a network includes a voltage source,and a power relay switch which can close to relay the voltage generatedby the voltage source to the devices in the network. The circuit furtherincludes a signature resistor for power source detection from one of theconnected devices. A load detector is connected to the switch and readsa load current flowing therethrough in order to detect a load in aconnected device and extract information about the connected devicebased on the load current.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings disclose illustrative embodiments. They do not set forthall embodiments. Other embodiments may be used in addition or instead.When the same numeral appears in different drawings, it is intended torefer to the same or like components or steps.

FIG. 1 illustrates power delivery over DiiVA for an upstream device anda downstream device connected through a serial link, in accordance withone embodiment of the present disclosure.

FIG. 2 illustrates the network topology for a power rail assigned to aDiiVA source device, in accordance with one embodiment of the presentdisclosure.

FIG. 3 illustrates the network topology for a power rail assigned to aDiiVA sink device, in accordance with one embodiment of the presentdisclosure.

FIG. 4 illustrates an exemplary POD (Power Over DiiVA) circuit, inaccordance with one embodiment of the present disclosure.

FIG. 5 provides a schematic overview of a DiiVA control protocol, inaccordance with one embodiment of the present disclosure.

FIG. 6 illustrates a physical view and a link view of the connectionbetween an active source device S4, POD clients S1-S3, and a POD serverTV, in accordance with one embodiment of the present disclosure.

FIG. 7 is a schematic diagram of one example of power delivery overDiiVA in a daisy chain configuration that includes one source device,one POD client, and one sink device.

DESCRIPTION

In the present disclosure, methods and systems are disclosed fordelivering power over DiiVA. Illustrative embodiments are discussed.Other embodiments may be used in addition or instead.

FIG. 1 illustrates power delivery over DiiVA between an upstream deviceand a downstream device connected through a serial link, in accordancewith one embodiment of the present disclosure.

In one embodiment, DiiVA implements serial link technology, i.e. sendsinformation in bit stream format. The physical layer device performsparallel-to-serial conversion, then sends serial bits through a cable,which in one embodiment may be constructed using copper wire. Aplurality of devices or nodes are connected through DiiVA in a daisychain, in which the first device is connected through DiiVA to a seconddevice, the second device is connected through DiiVA to a third device,and so on until the last device, with no loop-backs or webs.

In one embodiment, DiiVA implements differential signaling, using twowires. When sending the bit “1,” plus voltage is put on one wire, andminus voltage is put on the other wire, and when sending the bit “0,”the polarity is flipped.

In the embodiment illustrated in FIG. 1, an upstream device 105 isconnected to a downstream device 106 through a serial link for which asingle cable can be used. In one embodiment, the cable may be anEthernet CAT6 cable. Other embodiments may use different types ofcables, including but not limited to the CAT5 cable and the CAT7 cable.

In the illustrated embodiment, the cable includes four twisted pairwires, or differential pair wires. In the present application, a“differential pair wire” means two copper wires. In FIG. 1, the firstpair is shown as VL0+ and VL0−, where VL stands for video link; thesecond pair is indicated as VL1+ and VL1−; the third pair is shown asVL2+ and VL2−; the fourth pair is shown as HL+ and H−−, where HL standsfor hybrid link.

As shown in FIG. 1, the first three differential pair wires (i.e. thefirst six copper wires, namely VL0+ and VL0−, VL1+ and VL1−, and VL2+and VL2−) are used to transmit uncompressed video stream data, i.e. forthe video links. Three differential pairs are assigned for video data,because the video links require a large bandwidth. The fourthdifferential pair wire, namely HL+ and HL−, is used for the hybrid link,through which all user data (including but not limited to Ethernet data,USB data, forward audio data, backward audio data, and control data) aretransmitted.

Because in the illustrated embodiment DiiVA transmits all data(including but not limited to all video data and user data) with onlyfour twisted pair wires, DiiVA needs only eight connector pins. By usinga single cheap and readily available commercial cable (CAT6, as oneexample), containing only four differential pair wires, to transmitdata, cost effectiveness is significantly increased.

While traditional 48 V power delivery uses a transformer for inductancecoupling, high speed signals such as the multi-Gpbs signals supported byDiiVA cannot go through a transformer. In the embodiment illustrated inFIG. 1, double AC coupling is used to deliver power over DiiVA, insteadof using inductance coupling to couple the incoming signal.

In the illustrated embodiment, a first differential pair (VL0+, VL0−) ofthe serial link connection is doubly AC coupled using a first HPF (highpass filter) on one side and a second HPF on the other. Examples of HPFsare indicated with reference numeral 110. For clarity, not all the HPFsare labeled with reference numerals. A part of the first differentialpair between the first and the second HPFs are connected to a DC voltagesource on one side through a first LPF (Low Pass Filter), and to a loadon the other side through a second LPF.

In the illustrated embodiment, a second differential pair of the seriallink connection is doubly AC coupled with a third HPF on one side and afourth HPF on the other. A part of the second differential pair betweenthe third and the fourth HPFs are connected to a ground (shown in FIG. 1as GND 1) on one side through the third LPF and to another ground (shownin FIG. 1 as GND 2) on the other side through the fourth LPF. The DCvoltage source supplies a desired amount of current.

The notation VD0, VD1, VD2, VD3 shown in FIG. 1 stands for voltagelevel, downstream port, for the corresponding differential pairs; thenotation VU0, VU1, VU2, and VU3 shown in FIG. 1 stands for voltagelevel, upstream port, for the corresponding differential pairs.

When both sides of a differential pair wire is doubly AC coupled, asillustrated in FIG. 1 and described above, the medium in-between is in aDC floating state. In the illustrated embodiment, ferrite beads, shownas rectangular elements in FIG. 1, may be used to perform biasing. Inthis way, DC components of the power may be delivered withoutundesirably affecting the main high speed signal. Some examples of theferrite beads are indicated in FIG. 1 with reference numeral 120. Forclarity, not all the ferrite beads are labeled with reference numerals.

FIG. 2 illustrates the network topology for a power rail assigned to aDiiVA source device, in accordance with one embodiment of the presentdisclosure. FIG. 3 illustrates the network topology for a power railassigned to a DiiVA sink device, in accordance with one embodiment ofthe present disclosure. FIGS. 2 and 3 illustrate the same topology, withonly the direction reversed.

The power rail shown as PR0 in FIG. 2 corresponds to the differentialpairs denoted VL0 and VL1 in FIG. 1. The power rail shown as PR1 in FIG.3 corresponds to the differential pairs denoted VL2 and HL in FIG. 1. InFIGS. 2 and 3, power is delivered through the upper differential pair inthe power rails (PR0 and PR1, respectively) to a circuit 210, and thereturn or ground current flows to ground through the lower differentialpair in the power rails. In the embodiments illustrated in FIGS. 2 and3, signature resistor 220 is used for detections.

FIG. 4 is a schematic conceptual diagram of an exemplary POD (Power OverDiiVA) circuit, in accordance with one embodiment of the presentdisclosure. In one or more embodiments of the present disclosure, eachdevice in the DiiVA network that supports POD contains such a PODcircuit. In FIG. 4, both a POD circuit 401 for a downstream powerchannel (Tx (transmitter) to Rx (receiver)) and a POD circuit 402 for anupstream power channel (Rx to Tx) are illustrated. In one or moreembodiments, both the downstream power channel and the upstream powerchannel may have a power delivery capacity of about 500 mA at about 5 V,over 2 pairs of signals. Other embodiments may have different powerdelivery capacities.

In some embodiments (not illustrated), the downstream power channel andthe upstream power channel may be aggregated to provide more power inthe same direction.

In the illustrative POD circuits shown in FIG. 4, the reference numerals1, 2, 3, 4, 5, 6, 7, and 8 indicate copper wire numbering: “1,2” and“3,4” refer to the first two differential pairs of wires in the seriallinks connecting the devices in the DiiVA network, while “5,6” and “7,8”refer to the second two differential pairs of wires in the serial links.In the illustrated embodiment, one set of pairs (denoted “1,2” and“3,4”) are used to transmit power upstream, while the other set of pairs(denoted “5,6” and “7,8”) are used to transmit power downstream. Inother embodiments, different arrangements of the wires may be used totransmit power upstream or downstream.

In overview, the downstream POD circuit 401 includes: a voltage source410 configured to generate a voltage (or equivalently, electric power);a power relay switch 420 configured to relay, when closed, the voltagegenerated by the voltage source 410 to one or more of the connecteddevices; a signature resistor 430 connected to the switch 420 andconfigured for power source detection from one or more of the connecteddevices; and a load detector 450 connected to the switch 420 andconfigured to read a load current flowing therethrough so as to detect aload in one of the connected devices, and to extract information aboutthe connected device based on the load current. A controller (not shown)controls the opening and closing of the power relay switch 420. Theupstream POD circuit 402 includes the same circuit components arrangedin a symmetrically opposite configuration.

The information extracted by the load detector 450 may include withoutlimitation: information regarding the identity of the connected device;information regarding whether the connected device is powered on orpowered off; and whether or not the connected device needs a supply ofpower. The load detector may also detect removal of one of the pluralityof devices from the network, and/or connection of a new device to thenetwork.

When a load (typically one or more load resistors) is connected to thePOD circuit 401 or 402, the POD load detector 450 detects current flowtherethrough, to determine whether a device is connected, and if so, toobtain information about the connected device based on the load resistorvalue. For example, the POD load detector 450 may receive informationfrom a connected device indicating that the device is self-powered, andthus does not need to be supplied with power. Alternatively, the PODload detector 450 may receive information from a connected deviceindicating that the device needs to be supplied with power.

The POD circuit illustrated in FIG. 4 can perform a number of functions,including but not limited to: detecting power source from a neighboringdevice; detecting POD load in a neighboring device; detecting removal ofa device and/or connection of a new device; detecting a hot plug;detecting a POD client device; detecting power-on or power-off state ofa connected device; and relaying POD power, i.e. relaying POD currentfrom one side to the other.

FIG. 5 provides a schematic overview of a DiiVA control protocol,through which a source device 505 and a sink device (or display device)506 can exchange command packets can be exchanged through a commandsub-channel of a bi-directional hybrid link 534, in accordance with oneembodiment of the present disclosure. As seen in FIG. 5, video data aretransmitted in one direction only, i.e. downstream from a downstreamport 510 in the source device 505 to an upstream port 515 in the sinkdevice 506, through a video link 532.

Data packets are exchanged between the source device 505 and the sinkdevice 506 in both directions through the bi-directional hybrid link534. The hybrid link 534 thus allows high bandwidth bi-directional datato be transmitted between the source device 505 and the sink device 506which are connected through a daisy chain. The hybrid link 534 carriesdata for a number of interfaces in a packetized manner, includingwithout limitation: Forward Audio, Backward Audio, USB Data, EthernetData, and Command Channel.

The video link 532 is a point to point interface. In some embodiments,the video link 532 carries uncompressed high definition video data,although it is not limited to carrying only uncompressed video data. Thevideo data is carried over one or more lanes. In DiiVA, there may be 1,2 or 3 lanes of data. The clock to operate the video link is embedded inthe video data from the transmitter. While a uni-directional video linkis shown in FIG. 5, other embodiments of the present disclosure may usebi-directional video links.

FIG. 6 illustrates a physical layer view 610 and a link layer view 620,respectively, of one embodiment of an activation sequence in a daisychain connection of devices including: an active source device S4, PODclients S1, S2, S3, and a POD server or sink device, which in theillustrate embodiment is a TV.

The physical layer is responsible for physically transmitting andreceiving the actual data over the medium. In one or more embodiments,the medium is industry standard Cat-6 cabling, although different typesof medium can be used in other embodiments of the present disclosure.The data stream in the physical layer can be encoded in 8b-10b format.

The link layer is responsible for prioritizing and packetizing all formsof data and sending it to the physical layer for transmission. Theincoming data from the physical layer is de-packetized and forwarded toappropriate circuits for further processing.

The devices in the daisy chain can operate in an active mode, a PODmode, or an off mode. In the active mode, the device is fully turned on,i.e. locally powered and fully functional. In this mode, all video andhybrid link data are processed on chip using local power.

In the POD mode the video and hybrid link data is processed and servicedby the device. In this mode, the transmitter is able to communicate withthe receiver in entirety through the POD mode device. In the off mode,the IC and all of the circuits are turned off. No communication takesplace.

In one embodiment, each device in the daisy chain supports a ping pongprotocol, through which the device transmits back the data it received,and reverses the direction of the hybrid link, which is half-duplex.Every device connected through DiiVA supports this ping-pong protocol.

In some embodiments, the hybrid link is a point to point half duplexinterface, and is designed as a ping-pong or token passing interface. Ina ping-pong interface, one device sends a message and then waits for areturn message (or an acknowledgement or an idle packet), before sendinganother message. This operation can be summarized as follows: device Ahas the right to send and sends a packet; device B receives a packet;device B checks for correctness (no link errors); and device Backnowledges the packet.

In one embodiment, power delivery over DiiVA is performed for a systemthat includes a source device, a sink device, and at least one clientdevice connected between the source device and the sink device, alldevices connected to each other through a daisy chain. The source deviceis configured to generate and transmit digital video data. The sinkdevice is configured to receive the digital video data from the sourcedevice through a video link, and to exchange user data with the sourcedevice through a bi-directional hybrid link. In this embodiment, thesink device, when powered on, supplies power to the client device at alevel sufficient to allow the client device to enter a mode in whichuser data can flow through the client device. The sink device suppliespower to the source device through the client device so as to permit thesource device to be powered on.

FIG. 7 schematically illustrates an example of power delivery over DiiVAin a simple daisy chain configuration including one source device (inthe example shown in FIG. 7, a DVD player), one POD client (in theexample shown in FIG. 7, a set-up box), and one sink device (in theexample shown in FIG. 7, a TV). In the illustrated embodiment, the TVfirst sends power to the devices on the daisy chain. All source devicesnot locally powered (i.e. ‘turned on’) receive power from the TV overthe DiiVA cable. The TV is POD server and the source devices not locallypowered are POD clients. The client(s), in POD mode, operates the hybridlink in normal mode. All the devices discover each other through ahybrid link control protocol. The TV sends a command to the DVD player(source device) to turn itself on. The DVD player turns itself on,leaving the POD client mode, and sends video signals to the TV.

In sum, methods and systems have been described for delivering powerover DiiVA. The components, steps, features, objects, benefits andadvantages that have been discussed are merely illustrative. None ofthem, nor the discussions relating to them, are intended to limit thescope of protection in any way. While certain embodiments have beendescribed of systems and methods relating to power delivery over DiiVA,it is to be understood that the concepts implicit in these embodimentsmay be used in other embodiments as well. Numerous other embodiments arealso contemplated, including embodiments that have fewer, additional,and/or different components, steps, features, objects, benefits andadvantages. The components and steps may also be arranged and ordereddifferently. Nothing that has been stated or illustrated is intended tocause a dedication of any component, step, feature, object, benefit,advantage, or equivalent to the public.

In the present disclosure, reference to an element in the singular isnot intended to mean “one and only one” unless specifically so stated,but rather “one or more.” All structural and functional equivalents tothe elements of the various embodiments described throughout thisdisclosure, known or later come to be known to those of ordinary skillin the art, are expressly incorporated herein by reference.

What is claimed is:
 1. A media content system, the system comprising: a content source device; a content sink device, comprising a voltage source configured to generate a voltage and configurable for receiving media content data from the source device; a client device, physically connected with the source device through a first serial communication link and with the sink device through a second serial communication link, wherein the client device is configured to receive power from the sink device through the second serial communication link; wherein each of the first serial communication link and the second serial communication link comprises a respective first differential pair of wires and a respective second differential pair of wires, each of the first and second serial communication links being AC coupled at each respective end thereof through a respective High Pass Filter (HPF) to respective transceiver circuitry, located in each of the content source device, content sink device, and client device; and the content sink device is configured to supply the generated voltage via the second serial communication link to the client device, and the client device is configured to pass the generated voltage through to the content source device, and the transceiver circuitry in the client device is configurable to operate on power drawn from the content sink device, and the client device is configured to receive media content from the source device over the first serial communication link, and signal the received media content over the second serial communication link to the sink device.
 2. The media content system of claim 1, wherein the source device is configured to operate according to a protocol in which the source device turns itself on, using power drawn from the sink device, in response to a command from the sink device.
 3. The system of claim 1 wherein the source device and the sink device are configured to exchange user data with each other through a bi-directional hybrid link; and wherein the user data comprising one or more of: control data, Ethernet data, USB data, audio data, and bulk data.
 4. The system of claim 3, wherein each of the first serial communication link and the second serial communications link further comprise a third differential pair of wires and a fourth differential pair of wires; wherein the first, second and third differential pair of wires are used for the video links and are configured to transmit therethrough the video data; and wherein the fourth differential pair of wires are used for the bi-directional hybrid link and is configured to transmit therethrough the user data.
 5. The system of claim 4, wherein the third differential pair of wires is double AC coupled by a HPF on one side and by another HPF on an opposite side; and wherein the fourth differential pair of wires is double AC coupled by a HPF on one side and by another HPF on an opposite side.
 6. The system of claim 1, wherein the serial communication links are implemented in one of: a CAT5 cable; a CAT6 cable; and a CAT7 cable. 